1. Field of the Invention
This invention relates to the field of electrical connectors, and in particular to modules having arranged thereon a plurality of RJ contacts, electrical filtering and isolation components (sometimes referred to for convenience as filter components), and contact tails, the modules being arranged to be inserted into a shielded connector housing. The invention also relates to a multiple port (multiport) filter connector utilizing such modules, although those skilled in the art will appreciate that the modules could also be utilized in a single port connector housing.
The invention makes use of the principle of forming the ends of RJ contacts and contact tails into terminals to which the electrical filter components can easily be wired or otherwise connected as disclosed in copending U.S. patent application Ser. No. 08/866,107, filed May 30, 1997, and may also employ the filtering and isolation structure described in copending U.S. patent application Ser. No. 08/657,209, filed Jun. 3, 1996, both of which are incorporated by reference herein. In addition, aspects of the multiport filter connector of the present invention are disclosed in U.S. Pat. No. 5,531,612 (Goodall et al.), U.S. Pat. No. 5,639,267 (Loudermilk), and U.S. Pat. No. 5,775,946 (Briones), all of which are incorporated by reference herein.
2. Description of Related Art
Electrical connectors known as modular phone receptacles or jacks have been available for many years. Although connectors of this type were originally designed for use in telephone systems, they have found wide acceptance in a variety of other contexts. For example, modular jacks referred to as RJ connectors, which may be incorporated into single port or multiport arrangements, are now commonly used as input/output (I/O) interface connectors for enabling computers to communicate with each other and with a variety of peripheral equipment, and in particular as connectors between a local area network (LAN) and an appropriately configured interface card.
In order to receive a corresponding modular plug, the conventional modular jack or RJ connector is generally made up of a socket housing which includes a plug-receiving opening, opposed top and bottom surfaces joined by opposed side surfaces extending from the opening to a back surface, and a plurality of stamped, metallic elongated contacts mounted in the housing for engaging contacts of the corresponding plug. Each contact in this type of connector includes a contact mating portion at one end extending diagonally into the socket, a vertically extending lead portion at the other end, and a horizontally extending intermediate portion between the contact mating portion and the lead portion. Generally, the lead portions of the contacts are inserted directly into openings in the interface card and soldered in place.
Because the above-described type of modular jack or RJ connector is often used for digital communications, wires and contacts in this type of connector emit high frequency radiation which can interfere with other electrical equipment. In addition, circuitry to which the connector is connected are vulnerable to noise or transients induced in an incoming line by external sources. While adding filtering circuitry to the interface card can often be used to solve such problems, the difficulty of designing circuitry which meets current emissions requirements as well as space considerations suggests that inclusion of filtering or transient suppression capabilities in the connector would be desirable under certain circumstances, and in particular where the cost of providing on-board filtering exceeds the cost of adding filters to the connector.
Historically, attempts to add filtering or isolation components to interface connectors for LANs and similar applications have fallen into one of three categories:
1.) connectors in which the filter components are provided on a miniature circuit board fitted into or onto the connector, as described in U.S. Pat. No. 5,069,641 (Sakamoto et al.), or on circuit board traces applied directly to the connector, as described in U.S. Pat. No. 5,282,759 (Sakamoto et al.); PA1 2.) connectors in which the connector contacts are inserted through central openings in a ferrite block which forms the inductive component of the common mode filter, as described in U.S. Pat. No. 4,772,224 (Briones) and U.S. Pat. No. 5,397,250 (Talend); and PA1 3.) connectors in which the contacts are wrapped around the filter components, as described in U.S. Pat. No. 5,015,204 (Sakamoto et al.) and U.S. Pat. No. 5,139,442 (Sakamoto et al.).
Filters of the first type, in which the circuitry is provided on a printed circuit board, have the disadvantage that they are relatively expensive in comparison with corresponding circuitry mounted on a host interface card or circuit board, due to the limited space available within the standard connector and the consequent need for miniaturization. Filters of the second and third types, on the other hand, are simpler to install and use less expensive components, but have the disadvantage of failing to offer electrical isolation between input and output circuits, as a result of which the isolation circuitry must still be provided on the host circuit card.
More recently, techniques have been developed for including both "filtering" and isolation components within RJ connectors without the need for internal circuit boards while at the same reducing the number and complexity of assembly steps. Copending U.S. patent application Ser. No. 08/866,107, for example, discloses an arrangement for including within the connector both a common mode filter and an isolating transformer. In this arrangement, the mating portion of the contact structure is separated from the terminals or PCB tails extending from the connector to form the connection to circuits on the card on which the connector is mounted, and the components are arranged on a module and connected to the contacts by wire wrapping the leads of the components to ends of the contacts that have been formed into terminals.
The arrangement disclosed in copending U.S. patent application Ser. No. 08/866,107 greatly simplifies assembly of the connector, while increasing design flexibility because the terminal pattern and interconnections between the terminals can easily be varied without varying the housing footprint or the component mounting arrangement.
The present invention extends this concept still further by applying it to modules suitable for use in stacked or multiport RJ type connectors (although the modules can also be used in single port connectors), and by including on the modules various filter components in addition to the inductive or magnetic components described in U.S. patent application Ser. No. 08/866,107.
Multiport RJ type connectors are well-known, including modular versions in which the RJ contacts are arranged on modules that can be inserted into the RJ connector housing. U.S. Pat. Nos. 5,639,267 and 5,531,612 show typical examples of such connectors. However, none of the prior multiport connectors that utilize a modular design provides for inclusion of filter components on the modules, and none of the prior RJ component mounting arrangements, except for that of copending U.S. patent application Ser. No. 08/866,107 appears to be suitable for use in a multiport connector, where space is even more limited than is the case with a single port connector.
The modular RJ filter connector arrangement disclosed in U.S. Pat. No. 5,587,884 (Raman), for example, requires that the electrical filter and isolation components be mounted on a circuit board that is potted into the connector, and that is separate from the module to which the contacts are secured. Similarly, the arrangement disclosed in U.S. Pat. No. 5,687,233 requires a separate RJ contact module and isolation/filter component module. Such separate mounting of components would be difficult to achieve in a multiport connector.
In addition, even though these prior filtering and isolation arrangement provide for the inclusion of capacitors or other components in addition to inductors and transformers, the components are generally soldered to the circuit boards or modules to which they are mounted, which causes difficulties in the case of modules arranged to fit within a standard multiport RJ connector footprint. While solderless filtering arrangements for RJ connectors are also known, for example from U.S. Pat. No. 4,695,115 (Talend) and U.S. Pat. No. 5,387,250 (Briones), such arrangements are not suitable for use in filter modules of the type disclosed in the above-cited U.S. Pat. Nos. 5,587,584 and 5,687,233. Other prior isolation and/or filtering arrangements for RJ or similar connectors that have even less applicability to RJ contact modules or multiport filter connectors, are disclosed in U.S. Pat. Nos. 5,403,207 (Briones) and U.S. Pat. No. 5,736,910 (Townsend et al.).
Finally, the inclusion of LEDs in RJ filter connectors is known from a number of prior patents, including U.S. Pat. No. 4,987,317 (Pocrass), but it appears that no attempt has previously been made to include such LEDs in modular multiport connectors of the type described above.